code: def setUp(self):
      master_fd, self.fd = os.openpty()
      self.addCleanup(os.close, master_fd)
      self.stream = self.enterContext(open(self.fd, "wb", buffering=0))
      tmp = self.enterContext(
          tempfile.TemporaryFile(mode="wb", buffering=0)
      )
      self.bad_fd = tmp.fileno()
  
imports: import errno
  import os
  import sys
  import tempfile
  import unittest
  from test.support.import_helper import import_module
label_desc: Use image node_id 1 for calling the TestFunctions obj's underlying member method code with example usage: obj.setUp() without return types